Several technologies would benefit from a non-volatile integrated circuit analog memory. Voice recorders could use a small analog memory integrated circuit instead of a bulky mechanical tape drive. Electronic cameras could record images with no moving parts. Analog integrated circuit memory is needed to produce analog neural networks capable of reproducing the functions of animal nervous systems in electronic devices. Present non-volatile analog memories consist primarily of magnetic tape memories and floating-gate analog integrated circuit memories. Both of these have disadvantages compared to an analog ferroelectric memory. The disadvantage of magnetic tape memory is the use of mechanical systems to access the data. Tape systems are slow, bulky, require substantial power, are subject to mechanical wear-out, and are sensitive to shock and vibration. The data on the tape is stored sequentially, so the tape must be rewound or fast-fowarded to gain access to a particular piece of information.
Floating gate analog memories use devices referred to as EEPROMS (electrically-erasable programmable read-only memories). The EEPROM technology was originally used only as digital memory but has recently been adapted to serve as analog memory. These memories store data by means of electrical charge stored on an insulated (floating) gate of a MOSFET transistor. Each floating gate transistor stores one analog value, which is represented by the amount of current conducted by the transistor. The amount of current is regulated by the amount of charge stored on the floating gate for that transistor. The disadvantages of floating gate memories are that they are slow to write data, slow to erase data, and are very sensitive to radiation. The floating gate analog memory also requires complicated circuitry in the integrated circuit to perform the writing of the analog information.